The present invention relates to an electronic engine and transmission control system which is responsive to manipulation of manually operated control devices which can cause actions which result in increased load on the vehicle engine.
There are production agricultural tractors which have an electronically controlled engine and electronically controlled transmission, such as an infinitely variable transmission (IVT). Such a tractor can be operated in a fuel economy mode wherein the engine is controlled to run at a low engine speed. If, while in this mode, the operator manually commands the hitch to drop a hitch-mounted implement into the ground, or if the operator commands the ground-engaging elements of a towed implement, such as a ripper, to engage the earth, the tractor may stall because the transmission and engine cannot react quickly enough to overcome the increase in load. This can happen when such a tractor is being turned around at the end of a field and then driven a short distance at the end of the row. Then when the tractor is driven back into the field and the implement is dropped into the ground, the tractor may stall because the engine speed is too low.